Fermentation

Question 1

What were the six steps to ancient Egyptian brewing?

Answer 1

1) Grind up grains into a flour
2)Make dough and bake bread
3) Break bread into pieces and add to water
4) Wait until fermentation occurres
5) Filter bread pieces out
6) Drink the beer!

Question 2

What are the six steps to modern brewing?

Answer 2

1) Malting
2) Crushing
3) Mashing
4) Boiling
5) Fermenting
6) Filtering/Storing

Question 3

What is the malting process?

Answer 3

Barley is allowed to germinate, producing enzymes and smaller chain carbohydrates. It is then dried.

Question 4

What is the crushing process?

Answer 4

The malted barley is crushed into a fine powder.

Question 5

What is the mashing process?

Answer 5

The crushed malted barley is combined with water where the enzymes break the barley down into sugars.

Question 6

What is the boiling process?

Answer 6

The mash is boiled and has hops added to it.

Question 7

What does the boiling process do?

Answer 7

Inhibits spoilage from bacteria, inactivates enzymes, and contributes to clarification and flavor.

Question 8

What is the fermenting process?

Answer 8

The solution is added to a cask and yeast is added, converting the glucose into ethanol.

Question 9

What conditions are necessary for fermentation?

Answer 9

Anaerobic conditions, set temperature (usually cool).

Question 10

What is the essential process for vinegar?

Answer 10

Ethanol is converted by bacteria into acetate.

Question 11

What is the Orleans process for vinegar production?

Answer 11

A cask is filled half with wine. Holes are in the cask for air to into. A funnel exists to add wine below the surface layer. A valve exists to drain the vinegar below the surface layer. The surface layer is covered with the bacteria Acetobacter Acetii.

Question 12

What bacteria converts ethanol to acetate in the vinegar process?

Answer 12

Acetobacter Acetii

Question 13

What is the speed up Orleans process and how does it make the process more efficient?

Answer 13

Stages are added to the Orleans process. One cask empties to a different cask, which empties to a different cask and so on. The process is more efficient because there is a higher surface to volume ratio helping with aeration. Furthermore, a larger volume can be handled, making emptying/refilling more efficient.

Question 14

What is the 1850s improvement on vinegar production and how does it work?

Answer 14

The 1850s innovation involves a whole bioreactor set up. The vinegar is sprayed down onto solids that contain the bacteria, Acetobacter Acetii. Air is run countercurrent (from the bottom up). The wine/vinegar is recycled at the bottom, and pumped back to the top. This improves the aeration and surface to volume ratio dramatically.

Question 15

Who discovered that the conversion of milk to yogurt was caused by microorganisms?

Answer 15

Louis Pasteur

Question 16

What year did Louis Pasteur discover the catalyzing uses of microorganisms?

Answer 16

1857

Question 17

What are the two bacterium used to convert milk to yogurt?

Answer 17

Lactococcus lactis and Lactobacillus paracasei

Question 18

What is the “germ theory of fermentation?”

Answer 18

Microorganisms catalyze the conversion of raw materials into products

Question 19

What are the products of ABE fermentation?

Answer 19

Acetone, Butanol, and Ethanol

Question 20

What is the bacterium used for ABE fermentation and what condition does it need?

Answer 20

Clostridium acetobutylicum and anaerobic conditions

Question 21

What is the core concept learned from ABE fermentation?

Answer 21

Many conversions are possible via fermentation: just takes the right species and the right conditions.

Question 22

Who won the Nobel Prize for discovering Penicillin?

Answer 22

Sir Alexander Fleming, Ernst Boris Chain, Sir Howard Walter Florey

Question 23

What was the core lesson learned from the discovery and production of Penicillin?

Answer 23

Microorganisms can serve as a source of novel compounds and can be employed for their industrial production.

Question 24

What are the 8 general steps for Recombinant Protein Production?

Answer 24

1) Extraction of chromosomal DNA or plasmid DNA

2) Gene amplification by PCR

3) Plasmid linearization via restriction endonucleases (cleaves plasmid)

4) Ligation of amplified gene into the linearized plasmid

5) Introduction of the plasmid into production organisms

6) Cultivation of hosts in lab scale fermentation system

7) Separation of host/host proteins from product protein via centrifugation, precipitation, and chromatography

8) Conditioning and packaging of the product protein

Question 25

What is Metabolic Engineering?

Answer 25

The optimization of genetic and regulatory processes within cells to increase the cells production of the compound of interest.

Question 26

What are the steps for Metabolic Engineering?

Answer 26

1) Analysis of metabolic pathways
2) Identification of molecular targets for improvement
3) Application of genetic tools (gene overexpression, etc…)
4) Possess an improved production host

Question 27

What are the three general parts of bioprocessing?

Answer 27

Upstream processing, biotransformation and fermentation, and downstream processing

Question 28

What are the 9 steps of bioethanol production?

Answer 28

Upstream processing:
Delivery
Storage
Milling
Liquefication
Biotransformation and fermentation:
Saccharification
Fermentation
Downstream processing:
Separation
Distillation
Dehydration and storage

Question 29

What general steps typically occur before fermentation?

Answer 29

Raw materials require pretreatments such as: shredding, solubilization, and removal or toxic substances

Question 30

What general steps typically occur after fermentation?

Answer 30

The product requires: separation from cells, extraction, and purification

Question 31

What are the four general considerations for fermentation based processes?

Answer 31

1) Which organism can make my process of interest
2) Where do I find this organism?
3) Which technical requirements do I need for the process?
4) How to improve a fermentation process?

Question 32

What are the considerations for “how to improve a fermentation process?”

Answer 32

A) Which metabolic pathways exist in the organism (consider main products and by products)
B) How to optimize the process (consider better yields and increased activity).